Thin Film Transistor Liquid Crystal Displays (TFT-LCDs) and Organic Light Emitting Displays (OLEDs) occupy an important position in the field of flat panel display technology for their advantages such as lightweight, thinness, low power consumption, high brightness, high image quality and so on. At present, flat panel display devices such as liquid crystal TVs that are of large size, high resolution and high image quality, and in particular, dominate in the current market of flat panel display devices.
Currently, delay of image signal has become one of the key factors that restrict the development of the flat panel display devices of large size, high resolution and high image quality. Decrease of the resistance of a source electrode, a drain electrode, a gate line and a data line can reduce delay of image signal and hence improve image quality. At present, a method for decreasing the resistance of gate lines and data lines is to fabricate source electrodes, drain electrodes, gate lines and data lines by using metal Cu that has low resistivity. However, the method has the following disadvantages.
The adhesion of metal Cu is poor, and although a buffer layer of Mo, Ti, Mo alloy, Ti alloy or the like is typically used for improving the adhesion of Cu, the resulted TFT has a poor performance and thus image quality is poor due to the poor adhesion of Cu.